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1) Method to condition sealed crawl space and 2) ducting insulation removal OK?

1) Method to condition sealed crawl space and 2) ducting insulation removal OK?


  #1  
Old 12-12-17, 04:41 PM
L
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Question 1) Method to condition sealed crawl space and 2) ducting insulation removal OK?

Hello. I'm working on encapsulated my crawl space and these two questions will be coming up:

1. Which option do most people do to condition the air of a sealed crawlspace?

(Creating a Sealed Crawlspace - Fine Homebuilding)
Option 1: Install a continuously operating exhaust fan in the crawlspace that blows through a hole in the rim joist or an exterior wall. Make sure that the fan isn’t too powerful (1 cfm for each 50 sq. ft. of crawlspace floor area), because the makeup air entering the crawlspace is conditioned air from the house.

Option 2: Install a forced-air register to deliver supply air from the furnace or air handler to the crawlspace (again, 1 cfm for each 50 sq. ft.). Assuming the house has air-conditioning, this introduction of cool, dry air during the summer keeps the crawlspace dry.

2. Once the crawlspace is sealed, are there any rules about removing the insulation on ventilation ducting? It has got wet from condensation, so I'd rather remove it, but then was questioning why it's even needed once the space is sealed.

I appreciate your help!

Regards,
leaning
 
  #2  
Old 12-13-17, 01:08 PM
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2. Don't know why you'd go with 1. You treat the space like the rest of the house with a supply and return, if possible.

I don't insulate ductwork in a crawlspace which is insulated and open to the house air.
 
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Old 12-15-17, 04:23 AM
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conditioning sealed crawl space

I recently went from a ventilated crawl space to a sealed crawl space. Reinsulated the crawl space walls and covered with plastic and plywood. installed heating ducts from a newly installed furnace. Covered the dirt with a 6 mil poly. Ended up installing a vent in the crawl space for the return air. I could see moisture building up on the building from the air being forced out of the crawl space. Very happy with the outcome of all the work.
I would get rid of any insulation from the existing from the duct work.
 
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Old 12-17-17, 06:21 PM
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benamen,

installed heating ducts from a newly installed furnace. Ended up installing a vent in the crawl space for the return air. I could see moisture building up on the building from the air being forced out of the crawl space.
Can you dumb this this down for me? You have your furnace in the crawl space or above? You have a pipe from your furnace blowing out to the crawl space? Where is the vent sucking from and going to? Where are you seeing the moisture building up? (I think you're saying you blow into the crawlspace and then vent out through your crawlspace wall to outside and it's outside your are seeing the moist air. Is that right?)

And thanks everyone for the ventilation piping insulation tip. I've been wanting to rip it out for some time.

This is my winter project since the air is dryer and the crawlspace runs about 65F year-round so it's one of the few outside projects for this time of year.

Regards,
leaning
 
 

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